I think when I started at compare the market would be a good comparison as before that we were still called web designers and smartphones were too new.
My skills at the time were solid on the tools, good ability to wireframe, do high fidelity designs, discuss design concepts and theories and map user flows. What I needed to learn over the next few years could essentially be boiled down to 2 things: How businesses work and how to use data for design.
The first is about understanding how a business goes from idea or problem through funding, prioritisation, decisions making, design and development. Then understanding how that is measured in dollars and how you can measure improvements and return on investment.
This is an essential thing to learn so that you can be involved in the decisions that eventually lead to design briefs, I found myself often wondering why I was being asked (told) to design something I did not see the point in, and being able to speak money and business meant I was included earlier in the process and exert more influence earlier.
The second part is very tightly linked to the first as I found myself needing to justify to the business why my designs were “good” or “right” for the customers. I started diving into analytics and data, learning about how sales funnels work, how metrics are chosen and what they mean.
In parallel I was learning about user research and usability and how they can statistically prove an approach is valid and will work before the money is invested and time spent.
I guess the last unmentioned skill was people skills, in my earlier years I was a very blunt and abrupt person, and I was not so good at taking criticism. I often spoke with my body language a little too clearly what I thought of non designers opinions on design, and that didn’t win me any discussions or battles.
I was lucky to have really good managers who called me on my bullshit (pardon the term, it’s accurate though) and I learnt to be less attached to my work, and more attached to the outcome and problem than the steps to get there.